Predicted richness of arbuscular mycorrhizal fungal virtual taxa, root symbionts of crops and grasslands (VT per 100 m²).
Predicted richness of arbuscular mycorrhizal (AM) fungi expressed as virtual taxa (VT) per 100 m² soil sample, at 30 arcsec (approximately 1 km) resolution, colour ramp capped at 45 as in the published figure.
Source. Method and training data from Van Nuland, M. E. et al., "Global hotspots of mycorrhizal fungal richness are poorly protected", Nature (2025), doi:10.1038/s41586-025-09277-4, published under CC-BY 4.0; modelling code MIT (SPUN Underground Atlas).
3Bee reproduction, not the official SPUN product. The official rasters are not publicly downloadable, so the published model was re-run by 3Bee on covariates rebuilt from public sources, over Europe only, with its own validity mask. The reproduction was validated against SPUN's own exported predictions at every training point (Pearson r 0.996) and against the published Figure 2. This statement is required by CC-BY 4.0 and is removed when the official raster replaces it.
Reading the value. The model is global at ~1 km, so on a site of a few hectares the value describes the surrounding landscape rather than a field measurement. Open sea, the giant lakes, glaciers and deserts carry no value; inland lakes are interpolated from their shores.